Ethylmalonic acid

6148-64-7

601-75-2

Step 2: In a 250 mL three-necked flask equipped with a magnetic stirrer, a dosing funnel and a thermometer, monoethyl malonate potassium salt (17.77 g, 104.49 mmol) was dissolved in 18 mL of water. The reaction mixture was cooled in an ice bath and 8 mL of concentrated hydrochloric acid (about 2 mL) was added slowly and dropwise. Upon completion of the reaction, the mixture was filtered to remove the resulting KCl precipitate and the precipitate was washed with ether (3 x 50 mL). The filtrate was separated and the aqueous phase was further extracted with ether (3 x 50 mL). All ether phases were combined, dried with anhydrous MgSO4, filtered and concentrated under reduced pressure to give the colorless oily product ethylmalonic acid (13.45 g, 82% overall yield in two steps).